Strahle, Warren C.

An introduction to combustion by Warren C Strahle(
Book
)11
editions published
between
1993
and
1996
in
English
and held by
183 WorldCat member
libraries
worldwide

Aeroacoustics, STOL noise, airframe and airfoil noise : technical papers from AIAA 2nd Aero-acoustics Conference, March 1975,
subsequently revised for this volume by AIAA Aero-Acoustics Specialists Conference(
Book
)3
editions published
in
1976
in
English
and held by
35 WorldCat member
libraries
worldwide
"The papers in this volume reflect the progress in aeroacoustic research which has been made in the field of VTOL and V/STOL
aircraft noise. The research was directed mainly at developing better methods for predicting noise generation and propagation,
at determining the effects of pressure fluctuations on surfaces and interior noise, and at developing noise abatement techniques.
Among the topics covered are: scrubbing noise of externally blown flaps; propulsive-lift noise of an upper-surface-blown flap
configuration; the aeroacoustic characteristics of model slot nozzles with straight flaps; fluctuating pressures on aircraft
wing and flap surfaces associated with powered-lift systems; acoustic characteristics of a large upper-surface-blown configuration
with turbofan engines; the effect of forward speed on jet/flap interaction noise; and airframe noise in the far field."--Publisher
description

The computation of oblique shock wave characteristics for real gases by Warren C Strahle(
Book
)2
editions published
in
1961
in
English
and held by
7 WorldCat member
libraries
worldwide
A method is presented whereby oblique shock wave data for real gases may be readily obtained from real gas normal shock wave
data corresponding to the same upstream thermodynamic state. Although such solutions are well known for perfect gases there
appears to be no method available at this time to account for real gas effects. This method is only useful when the flow deflection
angle is the specified parameter instead of the wave inclination angle. There is no restriction to any gas com position since
the physics of the problem are completely contained in the normal shock characteristics. It is expected that primary use of
this method will be found in the study of vehicles for entry into planetary atmospheres. Because of the present uncertainty
of the characteristics of any of the planetary atmospheres it is not economically justifiable to compute oblique shock charts
for every conceivable model atmosphere. However, to even begin consideration of an entry vehicle requires that some normal
shock computations be made. (Author)

The thermodynamic properties and shock-wave characteristics of a model Venus atmosphere by Warren C Strahle(
Book
)2
editions published
in
1962
in
English
and held by
6 WorldCat member
libraries
worldwide
A model for the atmosphere of Venus is developed which may be useful for design studies of early atmospheric-entry vehicles
and for wind-tunnel simulation application. This atmosphere, derived from many questionable assumptions and scant experimental
data, consists of 85% carbon dioxide and 15% nitrogen by volume. The thermodynamic properties of the derived atmospheric composition
are presented over the temperaturepressure range of 150 to 24,000 K and 1/10,000 to 100 atm. To further assist in aerodynamic
entry calculations, normal-shock-wave characteristics of such an atmosphere are also presented. The fact that nitrogen is
present has important consequences in the thermodynamic properties and electron concentrations over the full temperature and
pressure range. The effects are of the order of the percentage of nitrogen addition to pure carbon dioxide. A graphical method
of obtaining oblique-shock-wave data and a method of obtaining electron concentrations at low temperatures are included as
appendixes. (Author)

Combustion generated noise in turbopropulsion systems(
Book
)4
editions published
between
1973
and
1975
in
English
and held by
4 WorldCat member
libraries
worldwide
The results are presented of a three year program investigating direct combustion noise in hydrocarbon-air flames. Tasks completed
during the final year of the program have been (1) the use of an exterior facility to investigate the noise from a large,
2 inch diameter burner and (2) the use of the anechoic facility to test flames stabilized by bluff body flameholders. Emphasis
in the program has been on premixed, fuel lean turbulent flames using ethylene, acetylene, propane and propylene fuels with
air as the oxidizer. Conclusions of practical interest are (1) combustion noise can be an important contributor to the overall
noise problem from turbopropulsion systems if the system extracts high shaft power, (2) it is not important to the nosie problem
from afterburning turbopropulsion systems, (3) if the noise output of a particular combustor type is known in one installation,
valid predictions may be made for the noise output of the same type of combustor in a different installation and (4) combustion
noise may be a contributor to the afterburner instability problem. (Author)

Combustion noise by Warren C Strahle(
Book
)4
editions published
in
1977
in
English and Undetermined
and held by
4 WorldCat member
libraries
worldwide

Rocket Research at Georgia Tech(
Book
)3
editions published
between
1979
and
1981
in
English
and held by
3 WorldCat member
libraries
worldwide
Progress is reported on four distinct projects which are administered as a group. The individual projects are identified as
tasks and reported on separately. A summary for each task follows: Task I. Work concerned improvement and application of the
impedance tube method for measurement of the presure-coupled combustion response of solid propellants and measurement of the
bulk damping in the product flow. Improvements included increaed sites and amplitude range of pressure measurements; increased
capacity of the data acquisition system; and a modified, more rapid data reduction program. Admittances and bulk loss coefficients
of nonaluminized and aluminized propellants were measured over a range of frequencies. Task II. Studies were continued on
external burning using an axisymmetric model at Mach 3. Tests with actual combustion of radially and axially injected hydrogen
are then reported. Outstanding performance values with significant base drag reduction is shown for injection and burning
directly in the near-wake (base burning). Task III. Investigations continued of the accumulation processes of aluminum on
the propellant burning surface that lead to formation of agglomerate droplets, the size of which dominates aluminum combustion.
Task IV. Experimental and analytical studies were continued on the subject of turbulence-induced pressure fluctuations in
a rocket-like cavity. A new theory was constructed for the generation of pressure disturbances by the turbulence. Undeniable
separation has been achieved between propagational and local pressure fluctuations, and the agreement between theory and experiment
are adequate

Audible and Ultrasonic Acoustic Emissions from Composite Solid Propellants(
Book
)3
editions published
between
1975
and
1977
in
English
and held by
3 WorldCat member
libraries
worldwide
The audible and ultrasonic acoustic emissions from deflagrating composite solid propellants were monitored and analyzed to
evaluate their potential use as diagnostics of the combustion and as a means for the study of fundamental burning processes.
A family of composite HTPB-AP propellants were tested which include a range of AP particle sizes, aluminized and nonaluminized
formulations, the effect of the addition of a catalyst, and the presence of an AFCAM aluminum coating. For the audible emissions,
the frequency behavior in the 0-10 kHz range can be explained by assuming the gas phase reaction time primarily controls the
oscillating frequency. The combustion noise efficiency, cannot be explained by the theories put forth, so the physical makeup
of the noise source is presently unknown. Analysis of the ultrasonic emission spectra indicates that there are no distinct
spectral features which can be used to identify a particular propellant by its acoustic signature. The rms emission levels,
however, can be used as a reliable, nonintrusive means for detecting flaws in the propellant, identifying bad burns, and measuring
burn rates. The overall level increases with increasing burn rate and chamber pressure and decreasing particle size. (Author)

Heterogeneous diffusion flame stabilization by Warren C Strahle(
Book
)3
editions published
in
1987
in
English
and held by
3 WorldCat member
libraries
worldwide
Analytical modelling and several experimental diagnostics were applied to an experimental flow in a two-dimensional subsonic
windtunnel with a backward facing step and provision for injection of inerts and combustibles through the porous floor behind
the step. The analytical techniques were based on a two equation modeling of turbulence with several variants of near wall
models and numerical approaches. Conventional experimental techniques, where applicable in the cold flow, included hot film
and pitot and anemometry. Laser - based diagnostics in the cold and hot flows for velocity and species concentration measurements
(both mean and instantaneous) included laser velocimetry in two components and Rayleigh molecular scattering. Major findings
in this complex turbulent flow with chemical reactions were a) there was a general agreement between analysis and experiment
in cold flow both with and without wall injection, b) this agreement occurred at the the most detailed level of turbulent
shear stress and mass transport, c) in hot flow there was acceptable agreement as to the gross features of the mean flow field,
but some theoretical details, such as reattachment length, went counter to experimental results

Acoustic signature from flames as a combustion diagnostic tool by Warren C Strahle(
Book
)3
editions published
in
1983
in
English
and held by
2 WorldCat member
libraries
worldwide
A program was conducted to investigate the feasibility of using the combustion noise acoustic output as a non-intrusive diagnostic
of some details of the combustion process. Investigated were an open premixed turbulent jet flame and a gas turbine combustor
converted to run on propane. The analysis links the acoustic pressure fluctuations to the distribution of heat release rate
fluctuations. Measurement of the sound field, yields in principle, the heat release rate fluctuation field. It was found,
however, that the analytical methods for this inverse problem are too sensitive to small experimental uncertainties. Consequently,
it appears that the method is not, in general feasible

Ultrasonic and audible acoustic emissions from composite solid propellants by Warren C Strahle(
Book
)2
editions published
in
1975
in
English
and held by
2 WorldCat member
libraries
worldwide
The primary task of this grant was to design, build and check out an acoustics apparatus to measure both audible and ultrasonic
acoustic emissions from burning composite solid propellants at pressures to 1000 psia. The check out was achieved with propellants
furnished by the Air Force Rocket Propulsion Laboratory. Preliminary results are reported on the acoustic emissions from these
propellants in the attachment. The apparatus description is also given in the attachment

Fractal image compression of Rayleigh, Raman, LIF, and LDV data in turbulent reacting flows by Warren C Strahle(
Book
)4
editions published
between
1990
and
1991
in
English
and held by
2 WorldCat member
libraries
worldwide
Fractal geometry analysis methods, analytical modeling and several experimental diagnostics were applied to an experimental
reacting flow in a two- dimensional subsonic windtunnel with a backward facing step and provision for injection of inerts
and combustibles through the porous floor behind the step. Experiments used laser velocimetry and Raman spectroscopy measurements
for two components of the mean and fluctuating velocity and the local nitrogen concentration, which was found in this flow
to be an accurate temperature sensor. The fuel used was hydrogen diluted with argon or nitrogen. Fractal geometry yielded
a new nonlinear adaptive filter and an interpolation method for improving the statistics of sparsely separated data points.
Analytical modeling was improved over from a prior program, and a two equation turbulent model now reproduces many of the
observed features of the reacting flow

Experiments and Analysis Related to External Burning for Propulsion(
Book
)2
editions published
between
1976
and
1977
in
English
and held by
1 WorldCat member
library
worldwide
An experimental study of base flow for a 2.25 inch diameter projectile at Mach 3 with and without simulated external burning
disturbances is reported. Base pressure and wake structure results from systematic variations in axisymmetric external compression
show that substantial base thrust can be produced and that the pressure and length scales of the external compression are
imposed on the near wake. Measurements with comparable axisymmetric and asymmetric compression contours show that peripherial
gradients reduce the base pressure rise. Furthermore, relatively large changes in the near wake length scales and a slight
reduction in the base pressure occur when the solid-blockage effects of discrete radial fuel jets are modeled with pegs mounted
near the base of the test projectile. (Author)

Combustion Noise Prediction: Entropy/Vorticity Effects(
Book
)1
edition published
in
1979
in
English
and held by
1 WorldCat member
library
worldwide
An experimental and theoretical program was conducted to see if entropy noise and vorticity-nozzle interaction noise, as well
as direct combustion noise, could be isolated in gas turbine combustor tests. Moreover, a unified correlation, with a rational
theoretical basis, was developed for direct noise from combustor rig tests. It was found that (a) vorticity noise was at least
as large as combustion noise; (b) entropy noise is minor but is large only at low frequency; (c) all noise sources are coherent
with each other over various frequency ranges; (d) with a choked nozzle termination the nose is higher frequency (approximately
2000 Hz) than heretofore believed; (e) some other unexplained noise source contaminated the results at low frequency; and
(f) the diffuser used caused additional coherent noise, probably through the vorticity source. A method for accounting for
the vorticity and entropy sources in combustor rig tests was indicated. (Author)